Leaking Gas

I bought a used 2008 YZ250 from a dealer here locally. When i bought the bike i started it rode it the whole 9 yards and everything was fine. so i loaded the bike up and got it home and decided to take it up the street just becasue i couldn't control myself :bonk:. i got back to my house and stopped and gas started pouring out of the overflow line from the carb.

I was thinking the same thing u are its probably a stuck float or the level needs adjusted so i pulled the carb and messed with it for a good hour and a half and got it to were it wasn't over filling so i put it back on the bike. i decided to start the bike for a min to make sure and what do u know after shutting down gas came pouring out again. i decided to call the dealer and to make a long story short sense it was used and i did buy the extended warranty they said i would have to pay for them to even look at it.

This is were i need help i pulled the carb back off i checked to see if the float well floated and it did. then i checked to make sure the needle that sits on the float sealed correct and it seals fine (both off and on the float) and it doesn't appear to be damaged. i can adjust the carb to were it doesn't leak when the carb is out of the bike and just hooked to the gas tank but as soon as i start the bike once the carb is back in it starts to over fill again. i have run out of ideas. i need help!!!

Have you oriented the carb correctly... make sure you swivel the carb so that the notch on the carb throat is seated between the two rubber tabs on the reed block boot.

If you've still got problems, I wouldn't be surprised if you need to adjust your float height again. It all takes a bit of trial and error (at least it did for me).

I've been through all of this before too. Just when I thought everything was sweat, it would overflow again.

Check the carb orientation, if you've still got the problem, lower the float height again.

You can also tap the float bowl with the back of a screwdriver to dislodge a sticky float... might be worth a try. Its possible that you've got a bit of crap in the carb (even thought its new). Don't be afraid to rip into the carb and give everything a good clean with compressed air and carb cleaner spray.

Berg

i had the carb placed right i figured those marks were for something...

i cleaned out the carb with cleaner it did have some gunk in it... i am thinking i will have to pull the carb again tomorrow and try to adjust it.

how much gas flow do i need coming out? do i need a steady stream or a couple drips. i know that the gas will stop coming out once the float is all the way up but it seems to never come...

http://www.thumpertalk.com/forum/showthread.php?t=841800

Just in case you're adjusting it the wrong way, here's the way to do it.

Also, what about your gasket? Is it sealing correctly? Did it see carb cleaner? If so, they grow and won't seal properly.

I basically set mine by trial and error - I'd set the height and reinstall, tip the bike from side to side (swinging through 45-60 degres each side) until no more fuel came out. I'd then check that tipping the bike right over would cause fuel to come out (to make sure that I hadn't lowered the float level too far).

Keep in mind that sometimes when you bend the float tang, it can bend back again (they seem to develop a bit of an elastic memory). This kept happening to me on my KTM. I'd set the level and it would be perfect, two days later it would bend back again and the bike would leak on the stand. This happened repeatedly.

I found that holding a small screwdriver against the tang pivot / bend point, whilst bending from the other end tended to bend the tang permanently to the desired position (creating a more defined bend). I've never had a problem since doing it this way, the float has held a constant level.

I really recommend giving the carb a thorough clean. Old fuel tends to glaze the carb components a little, perhaps this is upsetting the needle and seat. That's where the carb cleaner comes in handy, it'll break down any buildup. I've seen old fuel turn into a gel like substance too, which sits in the bowl. That probably doesn't help matters either :bonk:

Have you looked at this thread too:

http://www.thumpertalk.com/forum/showthread.php?t=412662

Berg

I found that holding a small screwdriver against the tang pivot / bend point, whilst bending from the other end tended to bend the tang permanently to the desired position (creating a more defined bend). I've never had a problem since doing it this way, the float has held a constant level.

Good tips! Have a portion of a square green dot! :bonk:

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